This smells fishy. First off, for $750 a caliper, you could have them rebuilt. They will hone the cylinders and replace the seals. Very serviceable!
The pitted rotors were not a problem except cosmetically. Many rotors are drilled already, so pits won't hurt them much, only slightly higher pad wear.
I do recommend a hard high-speed stop at least once every few weeks, and set regen to low for a few miles of stop and go. Also, in moist climates, change your brake fluid as soon as it turns yellow! It's hygroscopic, so it will suck moisture out of the air and then work on corroding your system from the inside out. Think the calipers are expensive? Check the price of the ABS valve body. I'd change it every 2 years minimum.
Tesla told me they spend a few hours trying to salvage the clipers but could only save one. Clearly it was my bad to not have them do a brake service but I was relying on Tesla to do what they thought they needed to do.
I had the car in every year (sometimes more).